A paper that came out in Science a fortnight before Christmas counts as the most important work on birds this century, by offering something that has eluded science for well over a century – a reliable tree of life for the world’s bird orders.
Biology was shaken some years ago by evidence implying that parrots and perching birds are closely related.
Links between the bird orders have proved extremely difficult to determine, and except for intelligence and a facility for learning songs, there is nothing about perching birds, which include honeyeaters, crows and sparrows, to suggest they are related to parrots. Their beaks and feet are very different.
The evidence that emerged was genetic, but some genetic studies did not find this relationship, so in my book Where Song Began I equivocated, describing the relationship as probable but not proven.
Lyrebirds are the ultimate high achievers: the world’s best songsters, the world’s oldest songbird line (along with scrub-birds), beloved cultural icons that grace our coins, and spectacular ecosystem engineers. They may be something else as well – birds that save human lives.
The ‘ecosystem engineer’ tag refers to the changes they make when they scratch the ground to unearth insects. One lyrebird in a year can shift 200 tonnes of soil and litter per hectare, causing soil erosion and uprooting ground-hugging plants, including, in Tasmania, an endangered orchid.
A new paper by Daniel T. Nugent and two colleagues takes the engineering concept further by concluding that lyrebirds reduce bushfire risk by burying leaf litter and uprooting the grasses and bracken that carry fire.